the Gulf of Mexico, Central America, Colombia and southern Brazil (Figure 2d).   Demographic Trends and Economic Growth Latin America faces major challenges in terms of population growth, economic development and the conservation and restoration of its coastal ecosystems.  In addition to the climate change impact, coastal areas are  also  exposed to different environmental conditions that may  vary  in a very short time scale  (e.g.,  tectonic activity) or over decades  (e.g.,  El Niño-Southern Oscillation  -  ENSO) or even with unpredictable occurrence  (e.g.,  hurricanes and tsunamis). As a first step to quantify populations and areas of land vulnerable to maritime and coastal phenomena, topographic contour levels can be used to assess exposure.  Land elevation is an interesting point for comparing the vulnerability of Latin American coasts with respect to other regions. In this context, a comparison of population growth in low  elevation  coastal  zones  (LECZ), defined here as the contiguous  low lying areas along the coast that are  less than 10 metres above sea level, is made with data from Africa, America, Asia, Europe and Oceania. Using the database generated by CIESIN (2013) and the World Bank (2014) a new database was produced with past population trends and a projection for 2100. The  LECZ  information was derived from the Shuttle Radar Topography Mission (SRTM), 3 arc second (~90m). In Figure 3 we show demographic trends  in Africa, America, Asia, Europe, Oceania  and Latin America.  In the  lower  panel, we show the millions of people  in LECZ  that are at risk in  the different regions and the estimated population for 2010 as well as for  2100.  African population growth is by far the  highest, followed by Latin America.  In the top panel we show the evolution of population densities  for  2010 and 2100  and the relative area of LECZ  and population living in LECZ  in 2010 with respect to the total of  each  region.  Excluding Antarctica, the amount of world land in the  LECZ  was  around 1.8%, by 2010, but 10% of the world population lived in these areas, with a density of 288 inhabitants per km2; this is expected to increase to 455 inhabitants per km2  by 2100. Today, 75% of the world population living in LECZ, is concentrated in Asia.  It is  clear, therefore  that most of the land at risk  in the world are areas of low elevation  in Asia and  the Americas.  Population density is estimated to be the  highest in  Africa and  Asia.  Because population growth is highest in Africa, the population at risk will also increase. The population at risk is lower in the Americas than in Europe  but  these  trends will reverse  as the population growth is higher in the Americas, especially in Latin America. The total population living in LECZ in Latin America for 2010  is 5.6% of  its  total population while  the land at risk is around 1.8% of its total land area.     Figure 2. Spatial distribution of key coastal ecosystems throughout Latin America (a) coral reefs (Spalding et al., 2001); (b) mangroves (Spalding et al., 2010a; 2010b); (c) seagrasses (Green and Short, 2003) and (d) oceanic and coastal persity (Tittensor et al., 2010a; 2010b).   By 2100, the expected population trends in these LECZ  are clearly different for each of the continents. For example, from 2000 to 2100 the population is expected to multiply in Africa, America, Asia, Europe and Oceania by 3.32, 1.78, 1.63, 0.90 and 1.31 times, respectively. In contrast, the population of Latin America is likely to multiply by 1.83 times, second to Africa, so while the total population living in Latin America  LECZ  is lower than the world average, except for Africa, the risk will increase substantially for Latin America compared to most of the world by 2100.  A summary of the population and population density for 1990, 2000, 2010 and that expected for 2100 in Latin American countries is presented in Figure 4, as well as the relative and total territory exposed in LECZ. From this figure it can be seen that in terms of population density Haiti and the Dominican Republic are the most vulnerable countries. In Latin America, the countries with most vulnerable populations and land at risk are Brazil, Mexico and Argentina, in descending order. Only Cuba is expected to experience a decrease in coastal population (-12%); the rest of the countries will experience population growth,  ranging from  30% (Mexico)  to  150% (Costa Rica) between 2010 and 2100. It is interesting to note that Costa Rica, Cuba, Guatemala, Nicaragua and El Salvador are the only countries where the relative population density is lower than the relative  LECZ  area.  Noticeably, tropical cyclones are very frequent in these countries.    拉丁美洲海岸侵蚀的现状英文文献和中文翻译(3):http://www.youerw.com/fanyi/lunwen_68458.html